Student ratings were analyzed in relation to individual- and class-level factors in a sample of about 5400 students in 168 classes in order to examine the relative importance of individual-and class-level factors in the determination of student evaluation of teaching quality. Hierarchical linear models showed that individual measures accounted for most of the variance. Prior interest and expected grade were the preponderant influence on students' ratings, in terms of level-2 variables, the effect of class size, professor's gender, and rank on parameters for level-1 variables was weak and insignificant. Because class-level variation was large (30% and 38%), other contextual factors should be explored in future studies of student evaluation of teaching effectiveness and multilevel analyses.